Self-cleaning heatsink for electronic components

Abstract

Systems for cooling semiconductor devices that can comprise a heatsink and a cleaning element for the heatsink. The heatsink can have fins spaced apart from each other by channels. The cleaning element can have a base and one or more arms extending from the base. The cleaning element can be positioned with respect to the heatsink such that each arm is aligned with a corresponding channel between the fins, and the arms are moveable between a flow configuration in which the arms are in the channels and a cleaning configuration in which the arms are outside of the channels.

I claim: 
     
       1. A system for cooling semiconductor devices, comprising:
 a plate configured to be thermally coupled to a semiconductor device; 
 fins projecting from the plate, wherein the fins are spaced apart by channels, wherein the plate has a top surface defining a floor portion between each pair of adjacent fins; 
 first cleaning elements, wherein each first cleaning element is in a corresponding channel at one end of the top surface and has a first base coupled to one of the floor portions; 
 second cleaning elements, wherein each second cleaning element is in a corresponding channel at an opposing end of the top surface and has a second base coupled to one of the floor portions; and 
 wherein the first and second cleaning elements are configured to move between a flow configuration in which contaminants can accumulate on the first and second cleaning elements and a cleaning position in which the contaminants are removed from the channels. 
 
     
     
       2. The system of  claim 1  wherein:
 each of the first and second cleaning elements comprises
 an arm having a capture portion and a flex portion, wherein the flex portion extends from the first and second base and the capture portion extends from the flex portion, and wherein the flex portion has a C-shape in the flow configuration such that the capture portion extends over the top surface portion of the plate and the flex portion moves such that the capture portion is removed from the channel. 
 
 
     
     
       3. The system of  claim 1 , wherein:
 when the first and second cleaning elements are in the flow configuration, contaminants can accumulate on the capture portions; and 
 when the first and second cleaning elements move from the flow configuration to the cleaning configuration, the flex portion changes shape such that the capture portion removes accumulated contaminants from the channel. 
 
     
     
       4. The system of  claim 1  wherein each of the first and second cleaning elements comprises a shape-memory material, wherein the shape-memory material is configured to change shape when heated above a threshold temperature and cooled below the threshold temperature and wherein the cleaning elements are configured to move between the flow configuration and the cleaning configuration when the shape-memory material changes shape. 
     
     
       5. The system of  claim 1  wherein:
 the first and second cleaning elements are configured to move from the cleaning configuration to the flow configuration when the first and second cleaning elements heat from below the threshold temperature to above the threshold temperature; and 
 the first and second cleaning elements are configured to move from the flow configuration to the cleaning configuration when the first and second cleaning elements cool from above the threshold temperature to below the threshold temperature. 
 
     
     
       6. A semiconductor device assembly, comprising:
 a semiconductor device having an integrated circuit; 
 a heatsink having a panel thermally coupled the semiconductor device and fins projecting from the panel, wherein the fins are spaced apart from each other by channels, and wherein the panel has a top surface defining a floor portion between each pair of adjacent fins; and 
 at least a first cleaning element at one end of the heatsink, the first cleaning element comprising a base attached to the floor portion and at least one arm aligned with one of the channels, and the arm having a flex portion extending from the base and a capture portion extending from the flex portion, wherein the flex portion has a bend in a flow configuration such that the capture portion extends in the one channel over the floor portion and the flex portion at least partially straightens relative to the bend to a cleaning configuration in which the arm rotates away from the floor portion. 
 
     
     
       7. The semiconductor device assembly of  claim 6  wherein at least the flex portion of the first cleaning element comprises a shape-memory material having a threshold temperature that is greater than room temperature, and wherein the shape-memory material is configured to cause the first cleaning element to move between the flow configuration and the cleaning configuration when the temperature of the cleaning element crosses the threshold temperature. 
     
     
       8. The semiconductor device assembly of  claim 7  wherein:
 the assembly further comprises additional cleaning elements that each comprise a base and an arm with a flex portion extending from the base and a capture portion extending from the flex portion, and the flex portion has a bend in a flow configuration and the flex portion at least partially straightens relative to the bend to a cleaning configuration in which the arm rotates outwardly; and 
 the bases of the additional cleaning elements are attached to the floor portions of the top surface of the panel of the heatsink such that the channels have one cleaning element at one end and another cleaning element at an opposing end.